"""
ETF资产模块 - 定义ETF资产类及其特有功能
"""

from typing import Dict, Optional

from FDAS.data.assets.fund import Fund
from FDAS.data.constants import ASSET_TYPE_ETF
from FDAS.core.exceptions import DataFetchError

class ETF(Fund):
    """
    ETF资产类
    
    继承自基金类，提供ETF特有的数据获取和分析功能
    """
    
    @property
    def asset_type(self) -> str:
        """获取资产类型"""
        return ASSET_TYPE_ETF
    
    def _get_basic_info(self) -> Dict:
        """获取ETF基本信息"""
        try:
            return self.provider.get_etf_basic_info(self.symbol)
        except Exception as e:
            return {
                "code": self.symbol,
                "name": "未知ETF",
                "asset_type": self.asset_type,
                "error": str(e)
            }
    
    def get_tracking_error(self) -> float:
        """获取ETF跟踪误差"""
        try:
            # 这里需要实现ETF跟踪误差计算逻辑
            return 0.0
        except Exception as e:
            raise DataFetchError(f"获取ETF跟踪误差失败: {str(e)}")
    
    def get_premium_discount(self, 
                            start_date: Optional[str] = None, 
                            end_date: Optional[str] = None) -> Dict:
        """获取ETF溢价/折价数据"""
        try:
            # 这里需要实现ETF溢价/折价数据获取逻辑
            return {
                "premium_discount": 0.0,
                "average_premium": 0.0,
                "max_premium": 0.0,
                "min_premium": 0.0
            }
        except Exception as e:
            raise DataFetchError(f"获取ETF溢价/折价数据失败: {str(e)}")